class Engineer{ String id; String name; Engineer({ this.id, this.name, }); factory Engineer.fromJson(Map parsedJson){ return Engineer( id: parsedJson["userId"] ?? parsedJson["id"], name: parsedJson["userName"] ?? parsedJson["name"], ); } factory Engineer.fromEngineer(Engineer department){ return Engineer( id: department?.id, name: department?.name, ); } @override bool operator == (Object other) => identical(this, other) || other is Engineer && id == other.id; @override int get hashCode => id.hashCode; Map toMap() { return { 'id': id, 'name': name, }; } }